That has come up before. We have a downstream change to disable that, and it's being upstreamed. Matt On Tue, Aug 28, 2018 at 12:29 PM, Mark Nelson <mark.a.nelson@xxxxxxxxx> wrote: > Hi Mark, > > Thanks for testing this! Is there any chance I could get you to create a > tracker ticket and upload your data here? > > https://tracker.ceph.com/projects/rgw > > I doubt very many people have run performance tests on sub-4k byte objects. > In bluestore at least, you'll also get hit by the min-alloc size which means > pretty significant write and space amplification. Out of curiosity, do you > know of many folks or applications that write out swift/S3 objects this > small? > > Mark > > On 08/28/2018 08:16 AM, Mark Seger wrote: >> >> I tried to include some data and the mail was rejected because of a >> suspected virus ;( >> >> Anyhow, running getput to talk to RGW via the swift API with varying >> object sizes I discovered GETs of objects with sizes less than 1448 bytes >> were taking 40msec longer which exactly corresponds to the delay the nagel >> alorgithm inserts under certain buffer alignment conditiions. I found this >> exact same problem with swift a number of years ago. >> >> The curious thing is I see in >> http://docs.ceph.com/docs/master/rados/configuration/network-config-ref/?highlight=public%20addr#tcp >> it says nagel IS disabled in rados but maybe not RGW? >> >> -mark >> > -- Matt Benjamin Red Hat, Inc. 315 West Huron Street, Suite 140A Ann Arbor, Michigan 48103 http://www.redhat.com/en/technologies/storage tel. 734-821-5101 fax. 734-769-8938 cel. 734-216-5309
